This invention relates generally to a device that prevents the spread of airborne diseases. More specifically, the invention relates to a portable device that traps pathogens found in cough/sneeze emissions which can be applied when a cough or sneeze is imminent.
Upper respiratory infections are a significant source of morbidity and indeed mortality throughout the world. Many viral and bacterial infections are transmitted through aerosolized droplets, which are emitted when an individual coughs or sneezes. Tuberculosis and influenza are perhaps the most notorious diseases transmitted in this way. The threat of airborne diseases has been exacerbated by the emergence of multiple-drug-resistant tuberculosis, threats related to bird-flu, and incurable respiratory infections known as SARS. While current widespread therapies are directed at alleviating the cough, and treating the causative organism, initiatives directed toward controlling the spread of such airborne diseases have been consistently ineffective.
The CDC (Center for Disease Control), the DDHS (Department and Human Services, USA), and the APIC (Association for Professionals in Infection Control and Epidemiology) currently make the following recommendations to limit the spread of airborne diseases:                1. Cover your mouth and nose with a tissue when you cough or sneeze.        2. If you don't have a tissue, cough or sneeze into your upper sleeve, not your hands.        3. Put your used tissue in the waste basket.        4. Clean your hands after coughing or sneezing.        5. Wash with soap and water.        6. After sneezing or coughing, clean yourself with an alcohol-based hand cleaner.        7. You may be asked to put on a surgical mask to protect others.        
These recommendations however are impractical for several reasons. First, these instructions require an infected person to always be close to a waste repository to dispose of the infected tissue and a sink to clean one's hands after coughing or sneezing. Second, coughing and sneezing are usually not isolated incidents but are continually repeated by the infected person. Washing one's hands is impractical after every cough or sneeze and may cause skin irritation. If these facilities are not continually available to the infected person and the person has to cough into their sleeve, the sleeve soon becomes a culprit in the spread of the disease until the shirt is washed.
Tissue is also not an adequate solution for covering the infected person's mouth and nose because tissue does not effectively protect the hand from contamination. These and other devices are not effective in preventing the spread of airborne diseases because they require the infected person's hand to come into contact with the contaminated “filter element”. This spreads the disease through contact with the infected person's hands.
Other more extreme solutions have been created in communities with particularly dangerous diseases. For example, in some countries and communities with an increased incidence of SARS, masks have been distributed to the general population. These masks are distributed to infected and uninfected persons alike to help stop the spread of the disease. Unfortunately, because of the social stigma surrounding people wearing masks and the feeling of confinement masks induce, the general population avoids and often does not wear these masks. Even the CDC is reluctant to take the step of recommending the use of masks.
Consequently, there has been a need to develop devices that can be applied only when a cough or sneeze is imminent. Three examples of these apparatuses are shown in U.S. Pat. No. 3,719,188 (“the 188 Patent”), U.S. Pat. No. 6,986,348 (“the '348 Patent”), and U.S. Pat. No. 7,013,494 (“the '494 Patent”).
The '188 Patent discloses a perforated container lined with a filter material that is attached to a mouth piece/nasal chute with a mouth piece cover. The walls of the perforated container have perforation to provide airflow through the container. The mouth piece is grasped in the user's mouth prior to a cough. The perforated container is shaped like a cigarette pack and is fixed in this configuration. Unfortunately, the device described in the '188 Patent leaves the filter element to some degree in contact with the user's hand, through the multiple side and bottom perforations. The expulsion of cough emissions will be into the hand holding the device, and although filtered, some hand contamination with seeping moisture through the holes is inevitable. Another deficiency is in the mouthpiece configuration. One must apply one's lips over the mouthpiece and create a seal with the lips prior to cough. This is cumbersome, especially when some degree of involuntary lip contracture occurs with cough.
Next, the '348 patent describes a T-shaped system of tubes and filters and one-way valves and screens. This hard plastic device also has a fixed configuration and is designed both for filtering microorganisms and for reducing the noise associated with the cough. The device is worn by the user. However, the device is cumbersome and is not designed for easy storage and transport.
Finally, the '494 patent describes a handkerchief pocket for holding a handkerchief so that the user does not have to handle the handkerchief during coughing. Pathogens may still be spread however because the device does not isolate the user from the handkerchief.
What is needed then is an apparatus for filtering pathogens expelled during coughing or sneezing that isolates the user from respiratory system emissions but that does not have to be worn as a mask.